MC68HC08GZ32 Datasheet, PDF (115/320 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 12
MSCAN08 Controller (MSCAN08)
12.1 Introduction
The MSCAN08 is the specific implementation of the MSCAN concept targeted for the Freescale
Semiconductor M68HC08 Microcontroller Family.
The module is a communication controller implementing the CAN 2.0 A/B protocol as defined in the
BOSCH specification dated September, 1991.
The CAN protocol was primarily, but not exclusively, designed to be used as a vehicle serial data bus,
meeting the specific requirements of this field: real-time processing, reliable operation in the
electromagnetic interference (EMI) environment of a vehicle, cost-effectiveness, and required bandwidth.
MSCAN08 utilizes an advanced buffer arrangement, resulting in a predictable real-time behavior, and
simplifies the application software.
12.2 Features
Basic features of the MSCAN08 are:
• MSCAN08 enable is software controlled by bit (MSCANEN) in mask option register (MOR2)
• Modular architecture
• Implementation of the CAN Protocol — Version 2.0A/B
– Standard and extended data frames
– 0–8 bytes data length.
– Programmable bit rate up to 1 Mbps depending on the actual bit timing and the clock jitter of
the phase-locked loop (PLL)
• Support for remote frames
• Double-buffered receive storage scheme
• Triple-buffered transmit storage scheme with internal prioritization using a “local priority” concept
• Flexible maskable identifier filter supports alternatively one full size extended identifier filter or two
16-bit filters or four 8-bit filters
• Programmable wakeup functionality with integrated low-pass filter
• Programmable loop-back mode supports self-test operation
• Separate signalling and interrupt capabilities for all CAN receiver and transmitter error states
(warning, error passive, bus off)
• Programmable MSCAN08 clock source either CPU bus clock or crystal oscillator output
• Programmable link to timer interface module 1 channel 0 for time-stamping and network
synchronization
• Low-power sleep mode
MC68HC08GZ32 Data Sheet, Rev. 3
Freescale Semiconductor
115